大螺距双源CT前瞻性心电门控冠状动脉成像在高心率患者中的应用  

Prospectively electrocardiogram-triggered high-pitch spiral acquisition dual-source CT coronary angiography in patients with high heart rates

作　　者：孙凯[1] 韩瑞娟[2] 马利军[1] 王利军[1] 王志清[1] 赵冬梅[1] 王刚[1] 

机构地区：[1]内蒙古包头市中心医院影像中心,014040 [2]内蒙古包头市中心医院心内科

出　　处：《中华临床医师杂志（电子版）》2011年第17期4962-4967,共6页Chinese Journal of Clinicians(Electronic Edition)

摘　　要：目的评价第二代双源CT大螺距前瞻性心电门控扫描模式(flashspiral)在高心率患者行CT冠状动脉成像(CTCA)中的图像质量及有效射线剂量,探讨最佳采集数据时间。方法接受第二代双源CT冠状动脉成像检查的1321例患者中,选择心率≥70次/min和心率<70次/min者各70例(A组和B组)。两组患者均采用flashspiral模式,A组患者采集图像时间为RR间期20%,B组患者为RR间期55%。比较两组患者CTCA图像质量与有效射线剂量等的差异性。结果 (1)两组患者年龄、性别、BMI、扫描时间比较,差异无统计学意义。(2)图像质量:A组不可诊断冠状动脉节段(评分3分)20段(2.1%),B组不可诊断冠状动脉节段14段(1.5%),两组不可诊断血管节段比较,差异无统计学意义。两组不可诊断节段均常发生在右冠状动脉和左冠脉回旋支。(3)射线剂量:A组平均有效射线剂量为[1.00±0.15(0.7～1.82)]mSv,B组[1.01±0.16(0.65～1.82)]mSv;两组有效射线剂量均在1mSv左右。结论 (1)高心率患者可采用大螺距进行前瞻性心电门控单个心动周期扫描成像。(2)扫描时间窗选择RR间期的20%成像图像质量好,心率上限宜在100次/min以下。(3)心率变异性是影响flashspiral扫描图像质量的重要因素。(4)高心率患者flash扫描的有效射线剂量低,仅约1mSv。Objective To assess the image quality and effective radiation dose of prospectively electrocardiogram-triggered(ECG)high-pitch spiral acquisition(flash spiral)mode of dual-source CT(DSCT)coronary angiography in patients with high heart rates.Methods From 1321 consecutive patients of high-pitch spiral acquisition dual-source CT coronary angiography,seventy patients with HR≥70 times per minute(group A)and seventy patients with HR<70 times per minute(group B)were prospectively included in this study.The start phase of image acquisition of the most cranial slice was selected at 20% of the R-R interval for group A and at 55% of the RR interval for group B.Assess the image quality and effective radiation dose of two groups.Results(1)There were no significant differences in age,sex,BMI and scan time between the two groups.(2)Image qualities:the segments with non-diagnostic image quality occurred(i.e.score 3)were no significant differences between group A and group B(2.1% vs.1.5%,P<0.001).Non-diagnostic image quality was mostly found in the right coronary artery and left circumflex artery in both groups.(3)The average effective radiation dose was [1.00±0.15(0.7-1.82)]mSv in group A and [1.01±0.16(0.65-1.82)]mSv in group B respectively.Conclusions DSCT coronary angiography can be performed in patients with high heart rates with high-pitch spiral acquisition mode.20% of the RR interval window is recommended for data acquisition for patients with HR >70 times per minute.The variability of HR is a major factor on image quality and the average effective radiation dose was about 1 mSv.

关 键 词：前瞻性心电门控技术 体层摄影术 X线计算机 冠状血管造影术 心率 

分 类 号：R816.2[医药卫生—放射医学]